Comparison of fruit growth and cell growth-related parameters during fruit development in ‘Gala’ and ‘Golden Delicious Smoothie’ (GS). (A) Fruit diameter, (B) cell number (layers), (C) relative cell production rate, and (D) cell area were measured from bloom until maturity. Closed circles represent ‘Gala’ and open circles represent GS. Error bar represents the standard error of the mean of four biological replicates (n = 4). Data presented here are from Figures 2 and 4 (thinned fruit only). Cumulative growing degree days after full bloom (GDD) were used to allow for comparison across the two genotypes. Insets display changes in fruit diameter, cell number and RCPR during early fruit development.